Graphite, Pencil, and Paper

[seve]

How does the graphite in a pencil leave a mark on a sheet of paper? Any ideas? My answer is due tomorrow, so a clue or answer would be great.

Thanks

[bjr_jyd15]

I would say that the friction is the main cause of the writing. When graphite is pushed down on paper, a force leaves marks on the paper, which would only happen with friction.

[The Bob]

How does the graphite in a pencil leave a mark on a sheet of paper? Any ideas? My answer is due tomorrow, so a clue or answer would be great.

Thanks

It is because of the structure of graphite. As graphite is made of Carbon they must bond together. The Carbons form 3 bonds, but carbon should form 4 with each otehr, therefore there is a free electron to move and be put on the paper. Also, as graphite is layers of carbon, some layers come off as well.

As a pencil is pulled along a piece of paper it leaves the graphite there.

Hope that helps.

The Bob (2004 ©)

[Tide]

Friction and shear cause cleaving between loosely bound sheets in the graphite lattice.